Army Boosts Battery Power but Not Weight

Army scientists have developed a new material that could enable lithium-ion batteries to perform at an unprecedented five volts as part of research to create improved power sources for the military.

Researchers at the US Army Research Laboratory have for years been studying how the components of batteries interact to develop a new material that, when added to a battery’s electrolyte, increases the energy density of batteries 30 percent, according to the Army. The material is one of several additives electrochemical researchers at the lab have discovered.

The breakthrough is part of ongoing work by the Army to reduce the amount of weight soldiers carry by reducing the weight of power sources such as batteries, Dr. Kang Xu, electrochemistry branch, US Army Research Laboratory, told Design News.

Kang Xu, an Army Research Laboratory scientist, is one of the inventors responsible for a 30-percent increase in energy density in lithium batteries. The work is part of ongoing research to increase the energy of batteries while lowering their weight, to reduce the burden soldiers carry in the field. (Source: Army)

Soldiers can carry up to 32lb of batteries in their packs, and the lithium-ion batteries they use now are typically non-rechargeable and contain 4.1 to 4.2 volt cells, Xu said. He and other researchers have discovered an additive that increases the energy of these batteries into the 5-volt range.

The new material, designed and synthesized by researchers, can break down into small F-Alkyl radicals that deactivate the oxidative catalytic centers on cathode surfaces. This process, called passivation, “prevents the bulk electrolyte components (salt, solvents) to be oxidized, and stabilizes the battery operation without these parasitic reactions,” allowing for less weight and more energy from the batteries.

The batteries now operate with two different cathode chemistries -- 4.6V (LiNiMnO4) and 4.8V (LiCoPO4) -- resulting in about a 30 percent energy density increase. However, the actual increase is dependent on a number of factors, including “the weight of packaging, amount of electrolytes used, and other parasitic weights,” Xu said.

"In general, increases in energy density are equivalent to a reduction of weight if the same amount of energy is considered. So the 5V battery can lead to either more energy in the same battery pack or less weight for a pack with the same energy."

So far, Army researchers have come up with eight additives belonging to three different families of compounds and are working on patents for several of them. All told, the work is a great leap forward that represents a “major energy increase,” Xu said. However, “there is still a long way for 5V batteries to make it into soldiers’ packs.”

Army research scientists are working on patents for this? Does this mean that the US government will license the technology for civillian applications, or that non-US military contract manufacturers can just forget it?

As much as I would like to complain about govt. spending just may be Dr Xu has something.

I was told by an upper level DOE guy at their annual Fuel Cell Seminar a few years ago that the majority of the weight that soldiers carry IS batteries. The next item is food and water. If for example a sniper in Afganistan has to sit on top of a mountain for a few days he needs power for his radios, night vision, etc. A generator is a problem because most technologies make noise when they are operating. Even a fuel cell needs plumbing, fans, etc that are a problem to design to be absolutely silent.

Robat, a sniper left on a hilltop for days isn't a regular load. But you make my point exactly that a generator is nessasary. It's probably the best use of a foolcell as such low level power needs is easily done by a small 10-50 wt fuelcell like are available to power laptops.

Next a solar panel or small wind/rivergen weighing a lb or 2 could supply needed power. And can be made stealth.

If hiking or while sitting, a foot/leg, gravity, etc motion generator is doable.

The best way is reducing power needs by more eff equipment because like on the grid, the power you don't use is the cheapest of all.

And why are soldier carrying such loads degrading their performance? Why not have hip hitched cart/packframe carrying it so the soldier doesn't have to hold up 100lbs they do too often, just pulling it instead. If it's a tent/bed made from kevlar it eliminates those and provides cover even when caught in the open at no extra weight.

If you add the "balance of plant" to the fuel cell i.e. air supply, fuel tank, pumps, valves, converters, inverters, etc. it isn't necessarily the most efficient source of power. The only reason that the shuttles, etc used them was due to the tons of H2 they had to have anyway for other things (like the big burner at the bottom).

The fuel cells only real advantage is that of being a battery that can be recharged instantly (assuming that their is a handy H2 source around your tent.

If you carry methanol the efficiency is a small fraction of that of a pure H2 cell. If you carry hydrogen it has to either be compressed (very low density storage), liquid (cryogenic problems) or hydride (weight problems).

Maybe solid oxide might work because it will run off most anything but operates at pretty high temps.

A few weeks ago, Ford Motor Co. quietly announced that it was rolling out a new wrinkle to the powerful safety feature called stability control, adding even more lifesaving potential to a technology that has already been very successful.

It won't be too much longer and hardware design, as we used to know it, will be remembered alongside the slide rule and the Karnaugh map. You will need to move beyond those familiar bits and bytes into the new world of software centric design.

People who want to take advantage of solar energy in their homes no longer need to install a bolt-on solar-panel system atop their houses -- they can integrate solar-energy-harvesting shingles directing into an existing or new roof instead.

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